Inboard-outboard marine drive

ABSTRACT

An inboard-outboard marine drive unit for boats wherein an outboard power leg is carried by an inverted yoke having a pair of downwardly extending, laterally spaced yoke arms receiving the power leg therebetween and a generally upwardly extending center post, the post being connected to the boat inboard of the stern transom. The inverted yoke is &#39;&#39;&#39;&#39;steerable&#39;&#39;&#39;&#39; in that steering of the power leg is accompanied by rotation of the yoke on its upwardly extending center post. Raising and lowering of the outboard power leg for trimming, tilting and kick-up is by rotation of the power leg about a generally horizontal axis extending between the spaced yoke arms.

United States Patent 1 Hurst 1 lNBOARD-OUTBOARD MARINE DRIVE [75]Inventor: John W. Hurst, Port Huron, Mich.

[73] Assignee: Chrysler Corporation, Highland Park, Mich.

221 Filed: Sept. 23, 1974 21 App]. NO.: 508,310

[52] U.S. Cl 115/41 R [51] Int. Cl B63h 5/12 [58] Field of Search 115/41R, 41 HT, 35

[56] References Cited UNITED STATES PATENTS 2,458,813 1/1949 Wanzer115/35 2,499,339 11/1944 Wanzer 115/35 2,536,894 1/1951 Wanzer 115/352,579,221 12/1951 Wanzer... 115/18 2,755,766 7/1956 Wanzer 115/352,953,335 9/1960 Kiekhaefer 115/18 3,003,724 10/1961 Kiekhaefer 248/43,006,311 10/1961 Hansson et a1. 115/35 3,008,445 11/1961 Frank 115/413,036,543 5/1962 Nolt 115/41 3,088.296 5/1963 Barker et a]. 115/413,128,741 4/1964 Benjamen 115/34 3,136,172 6/1964 Strang 74/3783.136.282 6/1964 Alexander, Jr. 115/35 3.136,283 6/1964 McCormick 115/353,136,284 6/1964 North 115135 3,136,285 6/1964 Kiekhaefer 115/353,136,287 6/1964 North 115/41 3,181,495 5/1965 Kiekhaefer 115/34 1 1July8, 1975 Primary Examiner-Trygve M. Blix Assistant Examiner-Stuart M.Goldstein Attorney, Agent, or Firm-Talburtt & Baldwin [5?] ABSTRACT Aninboard-outboard marine drive unit for boats wherein an outboard powerleg is carried by an inverted yoke having a pair of downwardlyextending, laterally spaced yoke arms receiving the power legtherebetween and a generally upwardly extending center post, the postbeing connected to the boat inboard of the stern transom. The invertedyoke is steerab1e" in that steering of the power leg is accompanied byrotation of the yoke on its upwardly extending center post. Raising andlowering of the outboard power leg for trimming, tilting and kick-up isby rotation of the power leg about a generally horizontal axis extendingbetween the spaced yoke arms.

11 Claims, 7 Drawing Figures INBOARD-OUTBOARD MARINE DRIVE BACKGROUND OFTHE INVENTION This invention relates to inboard-outboard marine driveunits for watercraft. particularly boats, wherein an inboard engine hasa rearwardly extending drive shaft coupled through universal joints topower transmission means in an outboard power leg to thereby drive apropeller carried at the lower end of the leg. The outboard power leg isaft of the stern and is mounted for pivoting on two mutually generallyperpendicular axes. It is therefore free to swing laterally for steeringthe boat while also being free to swing vertically such that the lowerend thereof may move rear wardly and upwardly in a tilting, trimmingand/or kickup motion relative to the steering of the boat in order toadjust the position of the power leg relative to the boat.

A main feature of the invention comprises the use of an inverted ordownwardly disposed yoke member having an upwardly extending center postand downwardly extending laterally spaced yoke arms. The outboard powerleg is carried on a generally horizontal axis by the yoke arms whereasthe yoke and outboard power leg together are connected to the boat bythe upwardly extending center post. The post provides a generallyvertical axis for steering and is inside the boat where it is notexposed to water. Other features of the invention will become apparentbelow.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a partially broken away andpartially sectioned port elevation of a boat with an inboardoutboarddrive unit embodying the invention;

FIG. 2 is an enlarged view of part of the port elevation of FIG. Iprimarily in section shown, among other features, the steerable invertedyoke and the double universal joints interconnecting the drive meansbetween the engine and the outboard power leg; the upper portion of theoutboard power leg is shown in a raised position in phantom lines.

FIG. 3 is a fragmentary view of the exhaust outlet for the unit taken inthe direction of arrow 3 in FIG. 1.

FIG. 4 is a fragmentary sectional view along lines 44 of FIG. 3.

FIG. 5 is an elevation showing the inverted yoke member by which theoutboard power leg is supported and connected to the boat;

FIG. 6 is a perspective stern view showing the boat and outboard powerleg of FIGS. 1 and 2, and

FIG. 7 is an enlarged view partially in cross section, taken generallyalong line 7-7 of FIG. 2, showing the pivoted connector attaching theforward ends of the hydraulic cylinders to the boat and showing inphantom the variable positions of the hydraulic cylinders when theoutboard power leg is turned laterally to port and starboard forsteering the boat.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawingFigures, the inboardoutboard unit includes outboard power leg 10 carriedaft of stern transom I2 on a partially shown boat or other watercraftI4. Outboard power leg 10 includes a propeller I6 carried by ahorizontal propeller shaft 18 which is driven by power transmissionmeans including vertical drive shaft 20 through a pair of bevel gearsgenerally indicated at 22 to propel the boat.

Vertical drive shaft 20 is supported within outboard power leg housing24 and is in turn driven by engine 26 mounted inboard of boat 14 througha horizontal drive shaft means 28 which extends rearwardly from theengine through a transom opening 30 and into a forwardly extendingbell-shaped portion 32 of housing 24. Intermediate its length horizontaldrive shaft means 28 is provided with a double universal jointgenenerally indicated at 34 in FIG. 2. Double universal joint 34 has itscenter substantially at the intersection of a steering axis and a tiltaxis of outboard power leg 10. These axes are described furtherhereinbelow.

The drive connection between the horizontal drive shaft means 28 andvertical drive shaft 20 includes a pair of horizontal spaced beveledgears 36 and 38, one of which is a forward gear, the other being areverse gear. Both are supported for rotation within suitable bearingson the upper end of shaft 20. A drive gear 40 carried on horizontaldrive shaft means 28 drivingly engages gears 36 and 38 and causes thelatter to rotate in opposed directions in the well-known manner. Aclutch element, generally indicated at 42, is disposed between beveledgears 36 and 38 and is carried by shaft 20 and slidable axially thereonto selectively engage gears 36 and 38 to complete the drive connectionbetween horizontal drive shaft means 28 and vertical drive shaft 20 tothereby drive propeller I6 in the desired direction. Clutch element 42also has an intermediate neutral" position between gears 36 and 38 inwhich position propeller 16 is rendered inoperative. Axial movement ofclutch element 42 relative to shaft 20 is effected by projecting member44 which may be actuated by means not shown. but typically a remotecontrol arrangement in boat 14 as is known in this art. The particulardrive connection and clutch arrangement described may be varied as itsspecific design is not critical to the invention.

The mounting means for outboard power leg 10, associated with the boatbetween the engine and outboard power leg comprises a one-piece casting46 although it may comprise inner and outer separate pieces positionedon each side of transom l2 and bolted or otherwise fastened together.Mounting means 46 includes an outer peripheral flange portion 48 whichfits sealingly (seal 49) around transom opening 30 and may be fastenedto transom 12 by a series of bolts as shown in FIG. 6. Mounting means 46extends through transom opening 30 and terminates interiorly of boat 14and transom 12 in an upper rigid mounting portion 50. The lower innerportion of mounting means 46 may include a lower mounting portion 52 forexhaust connection purposes. Mounting means 46 will preferably be shapedto include a hollow or indented area 54 (best shown in FIGS. 2 and 6) inthe upper portion 56 of house 24 when the outboard power leg I0 israised. Such an arrangement also provides clearance for steering in theraised position. Mounting means 46 may also carry a shaft supportstructure and seal arrangement generally indicated at 58 for supportinghorizontal drive shaft means 28 in opening 30 of transom 12. An annularflexible bellows 60 is disposed about double universal joints 34 and hasits ends secured forwardly to support structure 58 and rearwardly tohousing portion 32 as shown in FIG. 2. Exhaust receiving means 62 isfitted to lower mounting portion 52 for receiving exhaust gases fromengine 26. the interconnection therebetween not being shown for the sakeof simplicity. Such arrangements are well known. A flexible conduitmember 64 interconnects fittings 62 and housing 24 of outboard power legfor conducting engine exhaust interiorly of housing 24 and out exhaustoutlet 66, which is substantially at the water line when the outboardpower leg is in its normal operating position and the boat is on plane."The exhaust arrangement for the unit is shown in detail in FIGS. 3 and 4of the drawing. Exhaust outlet 66 is closed by a flexible flapper member67 which is normally closed to prevent the entrance of water into theunit. Due to its flexibility. it opens with exhaust pulses to allow theescape of exhaust gases to the water. The unit may also include a trimtab 69 for off setting torque reaction and reducing steering effort.

The upper rigid mounting portion 50 of mounting means 46 pivotallysupports an inverted yoke member 68 on a generally vertical axis toprovide for steering movement of the outboard power leg in a lateralside to side movement. Yoke member 68, best shown in FIG. 5, is invertedor downwardly extending laterally spaced yoke arms 72. Yoke member 68 isgenerally disposed inboard of transom 12 being mounted for rotation inupper rigid mounting position 50 by connection with upwardly extendingcenter leg 70 and suitable bearing means and fastening means indicatedat '74, 76 and 78 of FIG. 2. The inboard pivotal support of yoke member68 in upper mounting portion 50 provides the reguisite steering axis andsteering movement of outboard power leg 10 which is carried by yoke arms72 through its connection with housing portion 32 as best shown in FIG.6. This connection provides a generally horizontal axis extendingthrough yoke arms 72 at 80. Any suitable pivotal connection means may beutilized to establish the connection between housing portion 32 and yokearms 72. Carried as described above. it can be seen that there isprovided a steerable yoke member fitted inboard the boat in a compactmanner.

Steering is provided for by means of tiller arm 90 which is connected tothe upwardly extending center post 70 of yoke member 68 such thatlateral movement of tiller arm 90 causes yoke member 68 to pivot inmounting portion 50 thus turning yoke 68 and moving outboard power leg10 in a rotary steering movement, i.e., a lateral side to side movement.Remote control mechanisms and/or power steering mechanism may beattached to tiller arm 90 to allow steering to be accomplished fromother locations in the boat remote from the tiller arm. Sucharrangements are well known in the art and need not be described herein.

To control and limit the tilt, trim and/or kick-up movements of theoutboard power leg 10, a pair of extendable/collapsible hydrauliccylinders 82 and 84 are attached to each side respectively of power leg10 and to boat 14. In its preferred form. cylinders 82 and 84 arepivotally connected to support 86 which is itself pivoted for turning at88 on substantially the same axis as post 70 of yoke member 68. Such anarrangement provides for the maintenance of the same relative positionof the hydraulic cylinders 82 and 84 as outboard power leg 10 is turnedthrough its various steering movements. As shown in FIG. 7, thehydraulic cylinders can assume varied positions shown in phantomdepending on the extent of the steering movement. Thus there is providedan additional connection between the outboard power leg and the boat.Such cylinders can be readily designed to provide for trimming. tiltingand/or kick-up and such design details do not provide any part of thisinvention and need not be described herein since such matters are wellknown in the art.

Additionally. support 86 may include a pair of spaced lateral sidemembers 92 and 94 (best seen in FIGS. 1 and 7) for slidably receivingoutboard power leg housing 24 therebetween to provide lateral supporttherefor due to side loading of the unit. The extent of the engagementprovided by the side members may be varied by changing their size bothoverall and length.

What is claimed is:

1. In an inboard-outboard marine drive unit for boats having an inboardengine connected to an outboard power leg through drive shaft means anduniversal joint means, the improvement comprising a yoke member having agenerally upwardly extending center post directed oppositely fromgenerally downwardly extending laterally spaced yoke arms. meanspivotally mounting the power leg to the yoke arms about an axis to allowthe power leg to be rotated upwardly and rearwardly for trimming,tilting and kick-up, and means pivotally connecting the upwardlyextending center post of the yoke to the boat about an axis to allow theyoke and power leg to rotate laterally for steering the boat.

2. The inboard-outboard drive unit according to claim 1 wherein the yokemember is carried by the boat so as to position the axis of the post atthe horizontal drive center line inboard of the aft side of the boatstern transom.

3. The unit according to claim 2 wherein the yoke member is carried suchthat the axis through the yoke arms is also inboard of aft side of thestern transom.

4. The inboard-outboard drive unit according to claim 1 including meansin addition to the yoke member for connecting the power leg to the boatbelow the universal joint means.

5. The unit according to claim 4 wherein the means connecting the powerleg to the boat includes a lower support means pivotally attached to theboat for turn ing on a steering axis corresponding to that for theoutboard power leg and hydraulic cylinder means extending between thelower support means and the power leg for raising and lowering the powerleg about the axis provided at the yoke arm.

6. The unit according to claim 5 wherein the lower support means furtherincludes a pair of spaced lateral side members for receiving at least aportion of the power leg therebetween and providing lateral supportthereto.

7. In an article of manufacture for use with an inboard engine andrearwardly extending flexible drive means in a boat, an outboard powerleg including propeller means adapted for connection to the flexibledrive means, a downwardly disposed yoke member positioned forward of thepower leg and comprising an upwardly extending center post and a pair oflaterally spaced yoke arms extending downwardly from the center leg forcarrying the drive means thereon, first pivot means mounting the powerleg to the yoke arms for movement of the power leg about a generallyhorizontal axis. and second pivot means adapted for mounting the post ofthe yoke to the boat for lateral steering movement of the yoke and powerleg.

8. In an inboard-outboard drive in combination with a boat having atransom and an inboard engine with a drive means extending rcarwardlyfrom the engine through the transom. an outboard power leg includingpower transmission means connected to the drive means including a doubleuniversal joint interconnecting the engine drive shaft and the powertransmission means of the power leg, a propeller at the lower end of thepower leg driven by the power transmission means, a mounting memberfixedly associated with the boat between the engine and the power leg,an inverted yoke comprising an upwardly extending center post and a pairof downwardly extending laterally spaced arms, means pivotallyconnecting the center post of the yoke to the mounting member above theworking center of the double universal joint. and means pivotallyconnecting the power leg to the yoke arms for fore and aft swinging ofthe leg.

9. The combination according to claim 8 including means in addition tothe yoke member. for connecting the power leg to the boat.

10. The combination according to claim 8 wherein the center post of theyoke member is received by the mounting member inboard the aft side ofthe boat transom.

II. The combination according to claim 10 wherein the entire yoke memberis positioned inboard of the aft side of the boat transom.

1. In an inboard-outboard marine drive unit for boats having an inboardengine connected to an outboard power leg through drive shaft means anduniversal joint means, the improvement comprising a yoke member having agenerally upwardly extending center post directed oppositely fromgenerally downwardly extending laterally spaced yoke arms, meanspivotally mounting the power leg to the yoke arms about an axis to allowthe power leg to be rotated upwardly and rearwardly for trimming,tilting and kick-up, and means pivotally connecting the upwardlyextending center post of the yoke to the boat about an axis to allow theyoke and power leg to rotate laterally for steering the boat.
 2. Theinboard-outboard drive unit according to claim 1 wherein the yoke memberis carried by the boat so as to position the axis of the post at thehorizontal drive center line inboard of the aft side of the boat sterntransom.
 3. The unit according to claim 2 wherein the yoke member iscarried such that the axis through the yoke arms is also inboard of aftside of the stern transom.
 4. The inboard-outboard drive unit accordingto claim 1 including means in addition to the yoke member for connectingthe power leg to the boat below the universal joint means.
 5. The unitaccording to claim 4 wherein the means connecting the power leg to theboat includes a lower support means pivotally attached to the boat forturning on a steering axis corresponding to that for the outboard powerleg and hydraulic cylinder means extending between the lower supportmeans and the power leg for raising and lowering the power leg about theaxis provided at the yoke arm.
 6. The unit according to claim 5 whereinthe lower support means further includes a pair of spaced lateral sidemembers for receiving at least a portion of the power leg therebetweenand providing lateral support thereto.
 7. In an article of manufacturefor use with an inboard engine and rearwardly extending flexible drivemeans in a boat, an outboard power leg including propeller means adaptedfor connection to the flexible drive means, a downwardly disposed yokemember positioned forward of the power leg and comprising an upwardlyextending center post and a pair of laterally spaced yoke arms extendingdownwardly from the center leg for carrying the drive means thereon,first pivot means mounting the power leg to the yoke arms for movementof the power leg about a generally horizontal axis, and second pivotmeans adapted for mounting the post of the yoke to the boat for lateralsteering movement of the yoke and power leg.
 8. In an inboard-outboarddrive in combination with a boat having a transom and an inboard enginewith a drive means extending rearwardly from the engine through thetransom, an outboard power leg including power transmission meansconnected to the drive means including a double universal jointinterconnecting the engine drive shaft and the power transmission meansof the power leg, a propeller at the lower end of the power leg drivenby the power transmission means, a mounting member fixedly associatedwith the boat between the engine And the power leg, an inverted yokecomprising an upwardly extending center post and a pair of downwardlyextending laterally spaced arms, means pivotally connecting the centerpost of the yoke to the mounting member above the working center of thedouble universal joint, and means pivotally connecting the power leg tothe yoke arms for fore and aft swinging of the leg.
 9. The combinationaccording to claim 8 including means in addition to the yoke member, forconnecting the power leg to the boat.
 10. The combination according toclaim 8 wherein the center post of the yoke member is received by themounting member inboard the aft side of the boat transom.
 11. Thecombination according to claim 10 wherein the entire yoke member ispositioned inboard of the aft side of the boat transom.